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991.
992.
P Savagner AM Vallés J Jouanneau KM Yamada JP Thiery 《Canadian Metallurgical Quarterly》1994,5(8):851-862
We described previously that acidic fibroblast growth factor (aFGF), but not basic fibroblast growth factor (bFGF), can induce the rat carcinoma cell line NBT-II to undergo a rapid and reversible transition from epithelial to mesenchymal phenotype (EMT). We now find that NBT-II EMT is stimulated by keratinocyte growth factor (KGF) in cells grown at low density. Accordingly, a high-affinity receptor showing 98% homology to mouse FGF receptor 2b/KGF receptor was cloned and sequenced from NBT-II cells. Northern analysis indicated that mRNA for FGF receptor 2b/KGF receptor was drastically down-regulated within 1 wk in aFGF-induced mesenchymal NBT-II cells. This decrease coincided with an up-regulation of FGF receptor 2c/Bek, a KGF-insensitive, alternatively spliced form of FGF receptor 2b/KGF receptor. Functional studies confirmed that KGF could not maintain EMT induction on mesenchymal NBT-II cells. FGF receptor 1 and FGF receptor 2c/Bek could also support EMT induction when transfected into NBT-II cells in response to aFGF or bFGF. Such transfected cells could bind bFGF as well as aFGF. Therefore, EMT can be induced through different FGF receptors, but EMT may also regulate FGF receptor expression itself. 相似文献
993.
This in vitro study evaluated the influence of chromium content on bond strength and durability between nickel-chromium alloys and an adhesive resin that contained 4-methacryloxyethyl trimellitate anhydride. Three nickel-chromium alloys with different chromium content, as well as pure chromium and pure nickel metals, were bonded and tested for shear strength. After repeated thermocycling, shear bond strength decrease was lower in alloys containing high chromium content. Pure chromium metal demonstrated a 15.2% decrease, whereas pure nickel metal demonstrated the greatest (53.7%) decrease. The results suggest that nickel-chromium alloys with higher chromium content are desirable for 4-methacryloxy-ethyl trimellitate anhydride resin-bonded restorations. 相似文献
994.
Incidence and recognition of malnutrition in hospital 总被引:2,自引:0,他引:2
OBJECTIVES: To determine incidence of malnutrition among patients on admission to hospital, to monitor their changes in nutritional status during stay, and to determine awareness of nutrition in different clinical units. DESIGN: Prospective study of consecutive admissions. SETTING: Acute teaching hospital. SUBJECTS: 500 patients admitted to hospital: 100 each from general surgery, general medicine, respiratory medicine, orthopaedic surgery, and medicine for the elderly. MAIN OUTCOME MEASURES: Nutritional status of patients on admission and reassessment on discharge, review of case notes for information about nutritional status. RESULTS: On admission, 200 of the 500 patients were undernourished (body mass index less than 20) and 34% were overweight (body mass index > 25). The 112 patients reassessed on discharge had mean weight loss of 5.4%, with greatest weight loss in those initially most undernourished. But the 10 patients referred for nutritional support showed mean weight gain of 7.9%. Review of case notes revealed that, of the 200 undernourished patients, only 96 had any nutritional information documented. CONCLUSION: Malnutrition remains a largely unrecognised problem in hospital and highlights the need for education on clinical nutrition. 相似文献
995.
996.
997.
B Verdon JP Winpenny KJ Whitfield BE Argent MA Gray 《Canadian Metallurgical Quarterly》1995,147(2):173-183
OBJECTIVE: To determine the effects of stromelysin treatment on biochemical, histologic, and swelling characteristics of intact cartilage explants and to correlate these effects with changes in the functional physical properties of the tissue. METHODS: Bovine articular cartilage explants were cultured for up to 3 days in the presence or absence of recombinant human stromelysin (SLN). Damage to matrix proteoglycans and collagens was assessed and characterized by N-terminal sequencing and Western blot analysis, respectively. Explants were mechanically tested to assess the ability of the tissue to withstand cyclic and static compressive loads. RESULTS: Treatment with SLN resulted in a time- and dose-dependent loss of proteoglycans from cartilage explants, with significant loss seen after 3 days of exposure to 20 nM SLN: Histology indicated that initial loss of proteoglycans occurred in regions near the tissue surface and proceeded inward with increasing time of SLN exposure. SLN treatment resulted in degradation of matrix collagen types IX and II, and a concomitant increase in tissue swelling. This matrix degradation resulted in severe alterations in functional physical properties of the tissue, including compressive stiffness. The initial, focal loss of proteoglycans that resulted from SLN treatment was most accurately detected with high-frequency streaming potential measurements. CONCLUSION: Exposure of intact cartilage to SLN caused specific, molecular-level degradation of matrix molecules, which resulted in changes in the swelling behavior and marked deterioration of functional physical properties of the tissue. 相似文献
998.
The in vitro adherence of Staphylococcus aureus, Staphylococcus epidermidis and Escherichia coli to five commercially available prosthetic vascular graft materials was compared. The influence of precoating the segments with human plasma for 2 h was also studied. S35-methionine was used to radiolabel bacteria. The segments were exposed to bacterial suspensions of approximately 10(7) CFU/ml at 37 degrees C for 0.5-18h. Following repeated washing in phosphate buffered saline (PBS), radioactivity associated with the segments was measured. The adherence of the three clinically relevant bacterial species was higher to untreated Dacron than to gelatin or collagen impregnated/coated Dacron or to PTFE. Furthermore, precoating of grafts with human plasma reduced bacterial adherence to woven Dacron, had a little effect on gelatin coated Dacron, but increased the adherence to collagen treated Dacron and, in particular, to PTFE. 相似文献
999.
JP Salles M Gayral-Taminh J Fauvel I Delobbe M Mignon-Conté JJ Conté H Chap 《Canadian Metallurgical Quarterly》1993,268(17):12805-12811
By means of selective extraction in a Ca(2+)-chelating medium and immunoblotting, four annexins (I, II, V, and VI) were identified in both isolated rat renal glomeruli and rat glomerular mesangial cells. Upon 32P labeling of these cells in culture, annexin I was immunoprecipitated using a specific polyclonal antibody and was found to incorporate radioactivity in a constitutive manner. However, as with epidermal growth factor (200 ng/ml), addition of angiotensin II (10(-7) M), arginine-vasopressin (10(-7) M), or endothelin I (10(-7) M) resulted in a 2-3-fold stimulation of annexin I phosphorylation. The basal phosphorylation as well as the stimulating effect of angiotensin II were also detected by immunoblotting annexin extracts using an antiphosphotyrosine antibody. In addition, among various phosphotyrosyl proteins isolated from EGTA extracts by adsorption onto an anti-phosphotyrosine antibody, annexin I was specifically recognized by Western blotting using a monoclonal anti-annexin I antibody, and displayed the same increase upon cell stimulation with angiotensin II. Moreover, thin layer chromatographic analysis of phosphoamino acids present in immunoprecipitated [32P]annexin I showed an exclusive labeling of phosphotyrosine residue(s). Finally, the effect of angiotensin II was detectable after 10 min, maximal at 6 h, and present until 12 h of incubation. Using 12-h stimulation, tyrosine phosphorylation of annexin I displayed a maximum at 10(-7) to 10(-6) M angiotensin II. These data report for the first time the stimulation of annexin I tyrosine phosphorylation by biologically active peptides acting via receptors belonging to the superfamily of seven hydrophobic domain, G-protein-linked receptors, which lack an intrinsic protein tyrosine kinase. This suggests a possible role of annexin I in the mitogenic effect of angiotensin II, arginine-vasopressin, and endothelin I, which was previously observed on rat glomerular mesangial cells as well as on other cells. 相似文献
1000.
JP M?kel? M Iivanainen IP Pieninkeroinen O Waltimo M Lahdensuu 《Canadian Metallurgical Quarterly》1993,34(5):832-835
Propofol is a new, fast-acting intravenous (i.v.) anesthetic. Involuntary movements or epileptic seizures have occurred during or after propofol-induced anesthesia in approximately 50 reported cases; a third of the patients have had epilepsy. We report 5 patients with seizures in association with propofol anesthesia. A female epileptic patient developed severe status epilepticus; the other patients with short-lasting seizures had no previous epilepsy. Although propofol has been used in treatment of patients of status epilepticus, the risk of precipitation of epileptic seizures warrants consideration especially when planning anesthesia for epileptic patients. 相似文献